|Title||Determining the Nature of the Extreme Off-States in ULX Pulsars with NGC5907 ULX|
|Author||Dr Dominic Walton|
|Description||Following a series of remarkable discoveries, we now know that some of the most luminous ULXs are actually powered by highly super-Eddington pulsars (i.e. neutron stars), making them the most extreme accretors known. A number of the known ULX pulsars exhibit unusual .off.-states in which their X-ray flux drops by virgul2 orders of magnitude (or more). These off-states are fairly rare, but recent monitoring with Swift shows that NGC5907 ULX1, the most extreme of the ULX pulsars with L(X,peak)virgul1e41 erg-s, is now entering one. Here we propose three 60ks observations of NGC5907 ULX1 (180ks in total) designed to continue our efforts to determine the nature of these events. This is of critical importance, as these off-states may offer a means to determine the B-fields of these systems.|
|Publication||No observations found associated with the current proposal|
|Instrument||EMOS1, EMOS2, EPN, OM, RGS1, RGS2|
|Mission Description||The European Space Agency's (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESA's second cornerstone of the Horizon 2000 Science Programme. It carries 3 high throughput X-ray telescopes with an unprecedented effective area, and an optical monitor, the first flown on a X-ray observatory. The large collecting area and ability to make long uninterrupted exposures provide highly sensitive observations.
Since Earth's atmosphere blocks out all X-rays, only a telescope in space can detect and study celestial X-ray sources. The XMM-Newton mission is helping scientists to solve a number of cosmic mysteries, ranging from the enigmatic black holes to the origins of the Universe itself. Observing time on XMM-Newton is being made available to the scientific community, applying for observational periods on a competitive basis.
|Publisher And Registrant||European Space Agency|
|Credit Guidelines||European Space Agency, 2022-07-15T00:00:00Z, 088422, 19.16_20210326_1200. https://doi.org/10.5270/esa-[xxxxxxx]|